Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Selected Quarterly Financial Information [Abstract]
Net sales	$ 314,446	$ 320,946	$ 304,085	$ 274,512	$ 268,430	$ 285,247	$ 264,224	$ 236,303	$ 1,213,989	$ 1,054,204	$ 942,162
Gross profit	114,199	115,214	107,268	98,595	96,379	96,347	90,139	73,911	435,276	356,776	286,923
Net income (loss) attributable to common shareholders	$ 29,519	$ 30,908	$ 25,068	$ 18,526	$ (30,651)	$ 14,450	$ 13,179	$ 1,217	$ 104,021	$ (1,805)	$ 15,935
Earnings (loss) per share attributable to common shareholders
Basic	$ 0.59	$ 0.62	$ 0.50	$ 0.38	$ (0.62)	$ 0.29	$ 0.27	$ 0.03	$ 2.09	$ (0.04)	$ 0.33
Diluted	$ 0.58	$ 0.61	$ 0.49	$ 0.37	$ (0.62)	$ 0.29	$ 0.26	$ 0.02	$ 2.04	$ (0.04)	$ 0.32